Trends in delayed breast cancer diagnosis after recall at screening mammography

•The incidence of delayed breast cancer diagnosis after screening has decreased.•Most of these diagnostic delays are longer than 24 months.•Quality assurance should focus on screening programmes and hospitals handling recall. To determine the extent and characteristics of delay in breast cancer diagnosis in women recalled at screening mammography. We included a consecutive series of 817,656 screens of women who received biennial screening mammography in a Dutch breast cancer screening region between 1997 and 2016. During at least 3.5 years follow-up, radiological reports and biopsy reports were collected of all recalled women. The inclusion period was divided into four cohorts of four years each. We determined the number of screen-detected cancers and their characteristics, and assessed the proportion of recalled women who experienced a diagnostic delay of at least 4 months in breast cancer confirmation. The proportion of recalled women who experienced diagnostic delay decreased from 7.5 % in 1997−2001 (47/623) to 3.0 % in 2012−2016 (67/2223, P